Since last Earth Day

Three reports from the world’s preeminent scientific body on climate change

Since last Earth Day, the Intergovernmental Panel on Climate Change (IPCC) has issued three sobering reports. The first, issued in September 2013, looked at the physical science. It concluded climate change is now everywhere, its impacts are already unfolding, and humans are the “dominant cause.”

The second report, released in March 2014, looked at impacts and how people might adapt. It warned that that adaptation alone does not offer adequate protection, and that we risk pushing our climate system toward abrupt, unpredictable and potentially irreversible changes. It emphasized that world leaders have only about 15 years left to reduce carbon emissions enough to avoid catastrophic warming.

And the third report, just out this month, focused on economic costs of mitigation, and how governments can work together to moderate climate change. The report presents grounds for hope that the cost of mitigation would not cripple the global economy and may be less than commonly assumed. However, in terms of both adaptation and mitigation, the sooner we act, the lower the cost.

These IPCC reports, which together synthesize the evidence and the conclusions of thousands of scientific papers by hundreds of scientist/authors, make clear that climate change is not a political issue, that its effects are real, and that we must begin to view climate change as a risk management issue. All the evidence points to certain risk, and yet uncertainties remain, among them, what is the tipping point beyond which changes to earth’s climate system may become permanent? This scenario of risk and uncertainty brings to mind the commonsense need for insurance, and indeed a sensible insurance plan already exists in the form of the Copenhagen Climate Accord. In 2009, 114 countries agreed that warming this century must not increase by more than 3.6°F (2°C). To reach this goal, emissions will need to fall by 40 to 70% by 2050. We believe this is eminently achievable, if we have the will.